WoW.com made an interesting catch regarding WoW's temporary holiday bosses.
Remaking the Rare Holiday Loot Pinata
Currently, players must find a group for each boss the old-fashioned way (they tend to live in under-leveled dungeons, which max-level players cannot queue for in the LFG system). Once you get there, each player in the group, presuming that no one lies (you can verify this by checking your quest log to see how many groupmates also have the appropriate quest), can spawn the boss once for everyone's killing and looting pleasure. This would have caused problems for the random group finder, which does not currently screen out players based on who has or has not done a given daily quest.
With the change, the holiday bosses will be available ONLY via the dungeon finder (can't have a level 80 boss up and running in a level 26 dungeon once you remove the spawn quest). As with the emblems for completing daily dungeons (and soon battlegrounds), players will receive a special reward on their first kill of the boss per day - a bag with a chance to drop the rare loot formerly held by the boss.
Instead of five shots at a five-way roll against your group, you will now have one shot at loot that is guaranteed to be yours. Statistically, it's probably pretty close to a wash, unless you were sneaking in more than five boss kills per day by some method (such as agreeing to tank or heal for a desperate group, with the understanding that you had already used your summons). It also has the side effect of reducing the sheer number of the boss' common loot drops (such as necklaces, trinkets, etc) that enter the world, as most players will only kill and loot the boss for their regular loot once a day - I think I ended up with the complete set of trinkets from Coren Direbrew last brewfest, including the melee ones on my decidedly non-melee mage.
Beyond logistical convenience, the first thing that jumps out at me about this change is that it drastically reduces the penalty for failing the encounter. Under the old system, once you verified that everyone had their summons, it was in your best interest to quietly sit back and let someone else go first. That way, if your group proved incapable of beating the encounter and disbanded immediately, your summon would still be available.
Under the new system, the group can simply try, try again until they get it right. This could be viewed as reducing the already-low difficulty of the holiday bosses, or it could allow Blizzard to crank up the difficulty a bit more without unduly penalizing that hapless first player.
More broadly speaking, there is a clear message that WoW players now expect the convenience of the automated dungeon finder to come standard with as much content as possible. This is understandable, but how will it play with the system's general push towards easy content (to alleviate players' fears of fail pugs)? I'm not convinced that holiday events really are the place for difficult encounters, when they are already limited by both time and the random number generator to begin with, but what about elsewhere in the game?
At the risk of repeating myself, it is going to be very interesting how Blizzard balances the level 85 heroics when Cataclysm arrives.